L-APB is primarily used in scientific research to study the serotonin receptor system, particularly the 5-HT2A and 5-HT2B receptors. It serves as a valuable tool for understanding the mechanisms of serotonin signaling and its role in various physiological and neurological processes. Researchers utilize L-APB to investigate receptor binding, activation, and downstream effects, which can provide insights into conditions like mood disorders, anxiety, and schizophrenia. Additionally, it is employed in pharmacological studies to explore potential therapeutic applications or to develop new compounds targeting serotonin receptors. Its use is confined to laboratory settings, as it is not approved for medical or recreational purposes.